High pressure ball valve and seat

ABSTRACT

A ball valve for ultra-high pressure applications wherein the inner annular surface(s) of the valve seat(s) has an annular sealing face in sealing engagement with the flow control element, support surfaces adjacent the sealing face in contact with the flow control element, and vent grooves between adjacent support surfaces and between the sealing face and the support surfaces. A method to utilize the bidirectional ball valve involves rotating the valve stem and control element and maintaining a pressure of 275.8 MPa (40,000 psi) or more for at least 1 hour without leaking before opening or after closing the valve.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/790,433, filed Mar. 8, 2013, now U.S. Pat. No. ______, which claimspriority to U.S. Provisional Application Ser. No. 61/608,726 filed Mar.9, 2012, the disclosures of which are fully incorporated herein byreference.

BACKGROUND

Ball valves are often subjected to extremely high pressures andtemperatures in the various processes where they are used. Leaking pastseals associated with the rotatable closure members present operationalissues. The tendency for valves to leak increases under conditions ofhigh pressure and high temperature, which is known to occur in servicevalves which operate through a wide range of temperatures.

SUMMARY

The instant disclosure is directed to a two-way or bidirectional highpressure ball valve and a method using the bidirectional ball valve.

In one embodiment, a bidirectional valve comprises a valve bodycomprising an axial fluid flow bore disposed therethrough having aninlet end located opposite an outlet end and a flow control assemblylocated within a portion of the fluid flow bore,

the flow control assembly comprising a flow control element disposedbetween, and having an outer surface in sealing contact with an innerannular surface of an inlet valve seat and an inner annular surface ofan outlet valve seat, wherein the flow control element is rotatablebetween an open and a closed position;a valve stem extending from an outer end through a packing bore disposedradially around the valve stem in the valve body to an inner end of thevalve stem, wherein the inner end of the valve stem comprises aplurality of sides dimensioned and arranged to rotationally engage acorresponding recess having a corresponding number of sides disposedinto the flow control element, wherein a distance between the sides ofthe recess are dimensioned relative to a distance between the pluralityof sides of the first end of the valve stem to allow for an amount oflateral movement of the flow control element laterally between the fluidflow bore inlet end and the fluid flow bore outlet end such that apressure applied to the inlet end of the fluid flow bore results inlateral movement of the flow control assembly towards the outlet end ofthe fluid flow bore in an amount sufficient to produce sealing contactbetween an outer annular surface of the outlet valve seat with a portionof the valve body, such that a pressure applied to the outlet end of thefluid flow bore results in lateral movement of the flow control assemblytowards the inlet end of the fluid flow bore in an amount sufficient toproduce sealing contact between an outer annular surface of the inletvalve seat and a portion of the valve body, or a combination thereof,wherein at least a portion of the inner annular surface of the inletvalve seat, the inner annular surface of the outlet valve seat, or acombination thereof, comprise a sealing face dimensioned and arranged tosealingly engage a portion of the outer surface of the fluid controlelement, and wherein at least a portion of the inner annular surface ofthe inlet valve seat, the inner annular surface of the outlet valveseat, or a combination thereof, comprise a plurality of support surfacesdimensioned and arranged in physical contact with the outer surface ofthe fluid control element adjacent the sealing face.

In an embodiment, a method comprises providing a bidirectional valvecomprising:

a valve body comprising an axial fluid flow bore disposed therethroughhaving an inlet end located opposite an outlet end and a flow controlassembly located within a portion of the fluid flow bore, the flowcontrol assembly comprising a flow control element disposed between, andhaving an outer surface in sealing contact with an inner annular surfaceof an inlet valve seat and an inner annular surface of an outlet valveseat, wherein the flow control element is rotatable between an open anda closed position;a valve stem extending from an outer end through a packing bore disposedradially around the valve stem in the valve body to an inner end of thevalve stem, wherein the inner end of the valve stem comprises aplurality of sides dimensioned and arranged to frictionally engage acorresponding recess having a corresponding number of sides disposedinto the flow control element, wherein a distance between the sides ofthe recess are dimensioned relative to a distance between the pluralityof sides of the first end of the valve stem to allow for an amount oflateral movement of the flow control element laterally between the fluidflow bore inlet end and the fluid flow bore outlet end such that apressure applied to the inlet end of the fluid flow bore results inlateral movement of the flow control assembly towards the outlet end ofthe fluid flow bore in an amount sufficient to produce sealing contactbetween an outer annular surface of the outlet valve seat with a portionof the valve body, such that a pressure applied to the outlet end of thefluid flow bore results in lateral movement of the flow control assemblytowards the inlet end of the fluid flow bore in an amount sufficient toproduce sealing contact between an outer annular surface of the inletvalve seat and a portion of the valve body, or a combination thereof,wherein at least a portion of the inner annular surface of the inletvalve seat, the inner annular surface of the outlet valve seat, or acombination thereof, comprise a sealing face dimensioned and arranged tosealingly engage a portion of the outer surface of the fluid controlelement, and wherein at least a portion of the inner annular surface ofthe inlet valve seat, the inner annular surface of the outlet valveseat, or a combination thereof, comprise a plurality of support surfacesdimensioned and arranged in physical contact with the outer surface ofthe fluid control element adjacent the sealing face; androtating the valve stem such that the control element is in the closedposition prior to or after applying a pressurized fluid having apressure of greater than 275.8 MPa (40,000 psi) and a temperature ofgreater than or equal to about 200° C. to the inlet end of the fluidflow bore or to the outlet end of the fluid flow bore and maintainingthe pressure and temperature for at least 1 hour, wherein the fluid ismaintained by the valve without leaking.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross sectional drawing of one embodiment of aball valve according to the instant disclosure;

FIG. 2 is an exploded view of Section 2 shown in FIG. 1;

FIG. 3 is an exploded view of Section 3 shown in FIG. 1;

FIG. 4 is an exploded view of Section 4 shown in FIG. 1;

FIG. 5 is a frontal view an embodiment of a valve seat according to theinstant disclosure;

FIG. 6 is a side view of the valve seat shown in FIG. 5;

FIG. 7 is an isometric view of the valve seat shown in FIG. 5;

FIG. 8 is a frontal view of an embodiment of an upper or loweranti-extrusion ring according to the instant disclosure;

FIG. 9 is a side view of the upper or lower anti-extrusion ring alongline 9-9 shown in FIG. 8;

FIG. 10 is a frontal view of an embodiment of a top anti-extrusion ringaccording to the instant disclosure;

FIG. 11 is a side view of the top anti-extrusion ring along line 11-11shown in FIG. 10;

FIG. 12 is a frontal view of an embodiment of a sealing ring accordingto the instant disclosure;

FIG. 13 is a side view of sealing ring along line 13-13 shown in FIG.12;

FIG. 14A is a side view of a valve stem according to an embodiment ofthe instant disclosure;

FIG. 14B is a bottom-up view of the valve stem shown in FIG. 14A;

FIG. 15 is a top view of the flow control element according to anembodiment of the instant disclosure.

FIG. 16. is a schematic cross sectional drawing of another embodiment ofa ball valve according to the instant disclosure;

FIG. 17 is a frontal view of an embodiment of a thermoplastic ringaccording to the instant disclosure;

FIG. 18 is a side view of the thermoplastic ring along line 18-18 shownin FIG. 17;

FIG. 19 is an expanded view of a valve stem packing assembly accordingto an embodiment of the present disclosure;

FIG. 20 is a top, cross-sectional view of the assembly of the stem(FIGS. 14A, 14B) and ball (FIG. 15), showing application of fluidpressure from direction 121;

FIG. 21 is a top, cross-sectional view of the stem-ball assembly of FIG.20, showing application of fluid pressure from direction 120;

FIG. 22 is a top, cross-sectional view of the stem-ball assembly ofFIGS. 20, 21, showing rotational engagement of the ball by the stem.

DETAILED DESCRIPTION

Detailed embodiments are disclosed herein. However, it is understoodthat the disclosed embodiments are merely exemplary of the disclosure,which may be embodied in various forms. Specific structural andfunctional details disclosed herein are not intended to be limiting, butmerely illustrations that can be modified within the scope of theattached claims.

The instant disclosure is directed to a bidirectional ball valvesuitable for the passage of fluid under high pressure, and a method ofusing the valve in a high pressure environment.

Referring to the FIG. 1, in an embodiment bidirectional ball valve 10includes a valve body 12 comprising an axial fluid flow bore 14 disposedthere through having an inlet end 66 located opposite an outlet end 68and a flow control assembly 13 located within a portion of fluid flowbore 14. In an embodiment, flow control assembly 13 comprises a flowcontrol element 16 disposed between, and having an outer surface 15 insealing contact with an inner annular surface 91 of an inlet valve seat82 and an inner annular surface 99 of an outlet valve seat 84 (See FIG.4), wherein flow control element 16 is rotatable 18 between an openposition as shown in FIG. 1, and a closed position (not shown).

As shown in FIG. 1, in an embodiment, fluid flow bore 14, also referredto herein as fluid flow passage 14, extends axially from an inlet end 66to an outlet end 68 of the fluid flow passage of bidirectional ballvalve 10. Fluid flow passage 14 includes a flow control element 16, alsoreferred to herein as ball member 16 and/or ball 16, having an axialfluid flow bore 70 therethrough. In the embodiment shown, valve body 12comprises a plurality of components which include an upstream or inletportion 106 sealing engaged with, and connected to a downstream oroutlet portion 108.

Flow control element 16 is rotatable between an open and a closedposition as indicated by arrow 18 such that passage of fluid ispermitted when the fluid flow passage 14 when axial fluid flow bore 70of flow control element 16 is aligned with fluid flow passage 14, andcan prevent the passage of fluid when axial fluid flow bore 70 is notaligned with fluid flow passage 14 (not shown).

As shown in FIG. 1, bidirectional ball valve 10 may further include abracket 20 having a lower end 22 attached to valve body 12, and an upperend 24 spaced laterally therefrom defining an open access area 26between upper end 24 and valve body 12. Bidirectional ball valve 10further includes a valve stem 28 having a first end 30, also referred toherein as an inner end 30 of valve stem 28, engaging flow controlelement 16 and extending through a packing bore 32 in valve body 12 to asecond end 34, also referred to herein as an outer end 34 of valve stem28, centered in a bore 36 in bracket 20.

As used herein, the determination of inner (also referred to as lower)and outer (also referred to as upper) is merely in relation to theproximity of the surface to inner end 30 of valve stem 28. The inner orlower position being closer in proximity to the inner end 30 of valvestem 28 when assembled in the valve, as compared to the outer or uppercounterpart.

As shown in FIG. 1, valve stem 28 may further include a shoulder 38 withan enlarged outer diameter 40 (See FIG. 14A) formed on stem 28 in theopen access area 26 adjacent bracket 20. In an embodiment, outsidediameter 40 of shoulder 38 is less than an inside diameter of thebracket bore 42 disposed in bracket 20. In an embodiment, the valve stemfurther comprises a shoulder with an enlarged outer diameter formed onthe stem wherein the outside diameter of the shoulder is greater than aninside diameter of a portion of the valve body, a portion of a bracketattached to the valve body, a bushing attached to the valve body, or acombination thereof which is disposed around the valve stem between thesecond end and the shoulder to prevent the valve stem from being “blownout” when the valve is placed under pressure.

As shown in FIG. 1, bidirectional ball valve 10 may further include atop plate 44 attached to upper end 24 of bracket 20 on the surfacelocated opposite valve body 12. In an embodiment, top plate 44 comprisesa bore hole 46 centered about valve stem 28 having an inner diameterwhich is less than outer diameter 40 of stem shoulder 38. In anembodiment, bidirectional ball valve 10 may further include a contiguousshear bushing 48 disposed between stem shoulder 38 and top plate 44,wherein at least a portion of shear bushing 48 has an outside diameterlarger than the inside diameter of top plate bore 46, and an insidediameter less than outer diameter 40 of stem shoulder 38.

In an alternative embodiment, as shown in FIG. 16, a ball valve 200 mayinclude a shoulder 238 on a valve stem 228, within a valve body 212. Asis shown in FIG. 16, in an embodiment, ball valve 200 may furtherinclude a contiguous shear bushing 248 disposed between stem shoulder238 and valve body 212 located within a bushing well bore 210 withinvalve body 212. As shown in FIG. 16, ball valve 200 may further includea bottom plate 214 attached to valve body 212 to allow for removal ofvalve stem 228.

In an embodiment, bidirectional ball valve 10 may further include apacking gland 50 continuously secured around valve stem 28 in openaccess area 26 for securing valve stem packing assembly 52 around valvestem 28 in packing bore 32.

As shown in FIG. 1, and in the exploded view of FIG. 19, in anembodiment, valve stem packing assembly 52 comprises a plurality ofpacking rings having an inner diameter (e.g., see FIG. 9, inner diameter74), dimensioned to be disposable around valve stem 28, and an outerdiameter (e.g., see FIG. 9, outer diameter 75) dimensioned to belocatable within an inner diameter 33 of the packing bore 32 disposedradially around valve stem 28 in valve body 12.

In an embodiment, the valve stem packing assembly 52 comprises athermoplastic ring assembly 55 sandwiched between, and in physicalcontact with a sealing ring assembly 57 sandwiched between, and inphysical contact with an anti-extrusion ring assembly 59 and valve body12.

In an embodiment, as shown in FIG. 19, thermoplastic ring assembly 55comprises at least one thermoplastic ring 56 having an inner diameter 61(See FIGS. 17 and 18) dimensioned and arranged to sealingly engage valvestem 28 and an outer diameter 63 dimensioned and arranged to sealinglyengage inner diameter 33 of packing bore 32, and opposing annularsurfaces 65 and 67 dimensioned and arranged to physically engage annularsurfaces 75 and 77 of the sealing ring assembly 57. In an embodiment,sealing ring assembly 57 comprises an outer sealing ring 58 a having aninner annular surface 75 in physical contact with an outer annularsurface 67 of thermoplastic ring assembly 55, and an inner sealing ring58 b having an outer annular surface 77 in physical contact with aninner annular surface 65 of thermoplastic ring assembly 55, wherein eachsealing ring 58 a and 58 b has an inner diameter 80 (See FIGS. 12 and13) dimensioned and arranged to sealingly engage valve stem 28 and anouter diameter 85 dimensioned and arranged to sealingly engage innerdiameter 33 of packing bore 32.

In an embodiment, anti-extrusion ring assembly 59 comprises at least oneupper or outer anti-extrusion ring 60 a having an inner annular surface81 in physical contact with an outer annular surface 77 of outer sealingring 58 a.

In an embodiment, as shown in FIG. 19, anti-extrusion ring assembly 59may further comprise an inner or lower anti-extrusion ring 60 b havingan outer annular surface 81 in physical contact with an inner annularsurface 75 of inner sealing ring 58 b and an outer annular surface 83 inphysical contact with valve body 12. Accordingly, as shown in FIG. 19,outer anti-extrusion ring 60 a may be identical to inner anti-extrusionring 60 b, and may be arranged in valve packing assembly 59 rotated 180°perpendicular to a central axis. Likewise, sealing ring 58 a may beidentical to sealing ring 58 b, and the determination of inner (alsoreferred to as lower) and outer (also referred to as upper) is merely inrelation to the proximity of the surface to inner end, also referred toas the first end 30 of valve stem 28. The inner or lower position beingcloser in proximity to the inner end or first end 30 compared to theouter or upper counterpart. As is further shown in FIG. 19,anti-extrusion ring assembly 59 may further comprise a topanti-extrusion ring 64, and/or a plurality of rings which may be incontact with packing gland 50, as shown in FIG. 16.

In an embodiment, sealing rings 58 a and 58 b have a hardness which isgreater than the hardness of thermoplastic rings 56, and/or theanti-extrusion rings 60 a, 60 b, and 64, may have a hardness which isgreater than a hardness of the sealing rings 58 a and 58 b.

In an embodiment, the thermoplastic rings and/or the sealing rings maycomprise an engineering thermoplastic selected from the group consistingof a polycarbonate resin, a polyamide resin, a polyester resin, apolyether ether ketone resin, a polyacrylate resin, a polybutylenenaphthalate resin, a liquid crystal polyester, a polyoxalkylene diimidediacid/polybutyrate terephthalate copolymer, a nitrile resin,polyoxymethylene resin, a styrene-acrylonitrile copolymer, amethacrylonitrile-styrene copolymer, amethacrylonitrile-styrene-butadiene copolymer; an acrylate resin, apolyvinyl acetate, a polyvinyl alcohol, an olefinic chloride or otherhalide resin, a fluoride resin, a cellulose resin, a polyimide resin, apolysulfone resin, a polyacetal resin, a polylactone resin, apolyketones, a polyphenylene oxide resin, a polyphenyleneoxide/polystyrene resin, a polyphenylene sulfide resin, a styrene resin,an acrylonitrile-butadiene-styrene resin, a polyolefin resin, and acombination thereof.

Suitable engineering thermoplastics for use herein includepolycarbonates, such as poly(bisphenol-a carbonate); polyamide resins,such as nylon 6 (N6), nylon 66 (N66), nylon 46 (N46), nylon 11 (N11),nylon 12 (N12), nylon 610 (N610), nylon 612 (N612), nylon 6/66 copolymer(N6/66), nylon 6/66/610 (N6/66/610), nylon MXD6 (MXD6), nylon 6T (N6T),nylon 6/6T copolymer, nylon 66/PP copolymer, and nylon 66/PPS copolymer;polyester resins, such as polybutylene terephthalate (PBT), polyethyleneterephthalate (PET), polyethylene isophthalate (PEI), PET/PEI copolymer,polyether ether ketone (PEEK), polyacrylate (PAR), polybutylenenaphthalate (PBN), liquid crystal polyester, polyoxalkylene diimidediacid/polybutyrate terephthalate copolymer, and other aromaticpolyesters; nitrile resins, such as polyacrylonitrile (PAN),polymethacrylonitrile, polyoxymethylene (POM), also known as acetal, [1]polyacetal, and polyformaldehyde (Delrin™), styrene-acrylonitrilecopolymers (SAN), methacrylonitrile-styrene copolymers, andmethacrylonitrile-styrene-butadiene copolymers; acrylate resins, such aspolymethyl methacrylate and polyethylacrylate; polyvinyl acetate (PVAc);polyvinyl alcohol (PVA); chloride resins, such as polyvinylidenechloride (PVDC), and polyvinyl chloride (PVC); fluoride resins, such aspolyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF),polychlorofluoroethylene (PCFE), and polytetrafluoroethylene (PTFE);cellulose resins, such as cellulose acetate and cellulose acetatebutyrate; polyimide resins, including aromatic polyimides; polysulfones;polyacetals; polylactones; polyketones, including aromatic polyketones;polyphenylene oxide; polyphenylene oxide/polystyrene (Noryl),polyphenylene sulfide; styrene resins, including polystyrene,styrene-maleic anhydride copolymers, and acrylonitrile-butadiene-styrene(ABS) resin, polyolefins such as high density polyethylene, ultrahighmolecular weight polyethylene, combinations thereof, and the like.

In an embodiment, the thermoplastic rings of the valve stem packingcomprise a thermoplastic resin selected from the group consisting ofpolyvinyl fluoride (PVF), polychlorofluoroethylene (PCFE),polytetrafluoroethylene (PTFE); and combinations thereof. In anembodiment, the sealing rings of the valve stem packing comprise athermoplastic resin selected from the group consisting of a polyamide,polyphenylene oxide/polystyrene, polyoxymethylene (POM), polyether etherketone (PEEK), and combinations thereof.

In an embodiment, the thermoplastic rings of the valve stem packing mayhave a Rockwell R hardness determined according to ASTM D785 or anequivalent thereof, which is less than the Rockwell R hardness of thesealing rings. In and embodiment, the Rockwell R hardness of the sealingrings is less than the Rockwell R hardness of the anti-extrusion rings.In and embodiment, the thermoplastic rings of the valve stem packing mayhave a Rockwell R hardness of less than or equal to about 100 R, or lessthan or equal to about 90 R, or less than or equal to about 80 R, orless than or equal to about 70 R, or less than or equal to about 60 R,or less than or equal to about 50 R, or less than or equal to about 40R, or less than or equal to about 30 R, or less than or equal to about20 R, or less than or equal to about 15 R.

In an embodiment, the sealing rings of the valve packing may have aRockwell R hardness of greater than about 100 R, or greater than orequal to about 105 R, or greater than or equal to about 110 R, orgreater than or equal to about 115 R, or greater than or equal to about120 R, or greater than or equal to about 125 R, or greater than or equalto about 130 R determined according to ASTM D785 or an equivalentthereof.

In an embodiment, the Rockwell R hardness of any one of the sealingrings of the valve packing may be greater than the Rockwell R hardnessof any one of the thermoplastic rings of the valve packing by at least50 R units, or by at least 60 R units, or by at least 70 R units, or byat least 80 R units, or by at least 90 R units, or by at least 100 Runits, or by at least 110 R units determined according to ASTM D785 oran equivalent thereof.

In an embodiment, the anti-extrusion rings of the valve stem packing,which include the upper anti-extrusion ring, the lower anti-extrusionring, and/or the top anti-extrusion ring, may comprise brass, steel,titanium, silicon carbide, an at least partially austenitic steel alloy,or a combination thereof.

In an embodiment, the anti-extrusion rings of the valve stem packingcomprise an austenitic iron alloy further comprising chromium, nickel,manganese, silicone, nitrogen, carbon, molybdenum, titanium, niobium, ora combination thereof. Suitable examples include various stainlesssteels (SS) including XM-19, 303, 304/304L, 309, 310, 321, 347, 410,416, Inconel 718, 15-5, 17-4PH, 17-4 H1025, 17-4 H1075, 17-4 H1150, 17-4HH1150, NITRONIC 50, NITRONIC 60, A286, and combinations thereof.

In an embodiment, the anti-extrusion rings of the valve stem packingcomprises an austenitic steel alloy comprising iron, chromium, nickel,manganese, silicone, and nitrogen. Suitable examples include Nitronic 50and Nitronic 60 stainless steel.

As shown in FIGS. 8-11, in an embodiment, the top anti-extrusion ring 64has an inner diameter 72 which is greater than or equal to the innerdiameter 74 of the upper or lower anti-extrusion ring 60 a or 60 b. Inan embodiment, at least one of the anti-extrusion rings e.g., the topanti-extrusion ring 64, the upper anti-extrusion ring 60 a and/or thelower anti-extrusion ring 60 b comprise a chamfer 76 along an outerradial edge 78 of a first side 79 of the anti-extrusion ring 60.

In an embodiment, the plurality of rings in the valve stem packingassembly 52 are arranged such that the first side 79 of theanti-extrusion ring 60 is oriented in physical contact with sealing ring58.

In an embodiment, the upper anti-extrusion ring 60 a, the loweranti-extrusion ring 60 b, or both comprise a chamfer 76 along an outerradial edge 78 thereof.

As shown in FIGS. 9 and 13, in an embodiment, the upper anti-extrusionring 60 a and the lower anti-extrusion ring 60 b have an inner diameter74 which is greater than or equal to the inner diameter 80 of thesealing rings 58, the inner diameter 61 of the thermoplastic rings 56(FIG. 18), or both.

As shown in FIG. 1, fluid flow passage 14 includes an inlet seat 82 andan outlet seat 84. The seats 82 and 84 are spherically shaped tocooperate with the flow control element or ball 16, forming sealsagainst ball 16. Ball 16 is secured in fluid flow passage 14 betweeninlet seat 82 and outlet seat 84, and may be spaced from the bottom ofthe fluid passage 86 in a floating arrangement.

As shown in FIG. 1, in an embodiment, a spring 88 may be positionedbetween inlet seat 82 and valve body 12 to secure ball 16 between theseats 82 and 84. In an embodiment, spring 88 may be disposed within arecess 96 located between the inlet seat 88 and valve body 12, whereinrecess 96 and spring 88 have an outer diameter which is less than anouter diameter 88 of the inlet seat 82.

As shown in FIG. 16, in an alternative embodiment, a spring 88 may bepositioned between inlet seat 82 and valve body 212 and/or betweenoutlet seat 84 and valve body 212 to secure ball 16 between the seats 82and 84.

Inlet seat 82 and outlet seat 84 may be constructed from metal,preferably from the same material as ball 16, and may be at leastpartially formed during production, e.g., via lapping or other similarprocesses, such that each ball 16, inlet seat 82 and outlet seat 84 areindividually matched to each other as a set.

In an embodiment, at least a portion of the outer surface of the flowcontrol element, the inner surface of the packing bore, the fluid flowbore, the valve stem, the inner annular surface of the inlet valve seat,the outer annular surface of the inlet valve seat, the inner annularsurface of the outlet valve seat, the outer annular surface of theoutlet valve seat, the anti-extrusion ring, or a combination thereof mayinclude a spray and fuse coating comprising metals from Groups 6-12 ofthe periodic table of the elements alone, or in compounds comprisingelements from Groups 13-16 of the period table of the elements. Examplesinclude chromium carbide, tungsten carbide, chromium oxide, chromiumnitride, chromium boride, alone, or in combination with Mo, Ni, Cu, andthe like. Suitable examples include Colmonoy™ 5, 6, 43, 50, 56, 63, 69,72, 88, 225, 226, 227 (Wall Colmonoy Corp., Michigan, USA) and the like.

As shown in FIGS. 5-7, inlet seat 82 (and/or outlet seat 84) may beessentially identical, and comprise a sealing face 90 located on aninner annular surface 91 of each seat which sealing engages ball 16. Inan embodiment, inlet seat 82, outlet seat 84, or both comprise aplurality of vent grooves 98 laterally disposed between sealing face 90and an outer radial edge 100, and/or an inner edge 101 of the seat toprovide fluid communication between sealing face 90 and outer radialedge 100 and/or the inner radial edge 101 of the seat. In an alternativeembodiment, the valve seat may comprise a sealing face located near theouter radial edge which may comprise a plurality of vent grooveslaterally disposed between the sealing face and the inner radial edge ofthe seat.

In an embodiment, at least a portion of the inner annular surface 91 ofinlet valve seat 82, the inner annular surface 99 of outlet valve seat84, or a combination thereof, comprise a sealing face 90 dimensioned andarranged to sealingly engage a portion of the outer surface 15 of thefluid control element 16. In an embodiment, at least a portion of innerannular surface 91 of inlet valve seat 82, inner annular surface 99 ofoutlet valve seat 84, or a combination thereof, comprise a plurality ofsupport surfaces 115 dimensioned and arranged in physical contact withouter surface 15 of the fluid control element 16 when assembled in flowcontrol assembly 13. In an embodiment, support surfaces 115 are locatedadjacent to sealing face 90, and may be separated from sealing face 90by annular grooves 117. In an embodiment, inner valve seat 82, outervalve seat 84, or a combination thereof comprise a plurality of ventgrooves 98 laterally disposed into inner annular surface 91 and/or 99 ofvalve seats 82 and/or 84 between each of the plurality of supportsurfaces 115 and an outer radial edge 100 of the valve seat, an innerradial edge 92 of the valve seat, or a combination thereof.

In an embodiment, vent grooves 98 are disposed into inner annularsurface 91 and/or 99 in an amount sufficient to prevent spreading ofcracks which may occur in a coating applied to inner annular surface 91and/or 99, e.g., a spray and fuse coating 131, and/or which may act as astopping point for cracks which may occur in a coating applied to innerannular surface 91 and/or 99, or the like.

As shown in FIG. 3, inlet valve seat 82, also referred to herein as aninlet seat 82 may comprise an outer sealing surface 94 dimensioned andarranged to sealing engaged with a portion of the valve body 12 locatedon the upstream side, also referred to herein as an inlet side or inletend 66 side of ball 16.

As shown in FIG. 4, outlet seat 84 may comprise an outer sealing surface93 dimensioned and arranged to sealing engage a portion of the valvebody 97 located on the downstream or outlet side 68 of ball 16.Accordingly, in an embodiment, the valve may be a bidirectional valve.

As shown in FIG. 4, in an embodiment, outlet seat 84 may be attached tovalve body 12 using a plurality of threaded members 102 engaged with anouter radial edge 100 of outlet seat 84 and valve body 12.

As shown in FIG. 15, valve stem 28 may engage ball 16 in a recess 104dimensioned and arranged to receive valve stem first end 30. In anembodiment recess 104 disposed in the flow control element, e.g., ball16, is dimensioned and arranged to receive the valve stem first end 30,wherein recess 104 is oversized relative to the valve stem first end 30by an amount sufficient to allow movement of the flow control element,e.g., ball 16 towards either end of the fluid flow bore when an amountof pressure is applied to an opposite end of the fluid flow bore. Asused herein the term recess 104 is “oversized” relative to first end 30refers to the outer diameter of recess 104 being intentionally madelarger than the inner diameter of first end 30 by an amount greater thannormal tolerances would require. In other words, the fit is purposely“loose” as is well understood by one of minimal skill in the art.

Accordingly, in an embodiment, valve stem 28 extends from outer end 34through packing bore 32 disposed radially around valve stem 28 in valvebody 12 to inner end 30 of valve stem 28.

As shown in FIGS. 14A and 14B, in an embodiment, inner end 30 of valvestem 28 comprises a plurality of sides 31 dimensioned and arranged torotationally engage a corresponding recess 104 (See FIGS. 15, 20-22)having a corresponding number of sides 110 disposed into flow controlelement 16, wherein a distance 112 between the sides 110 of recess 104are dimensioned relative to a distance 113 between the plurality ofsides 31 of first end 30, also referred to as inner end 30, of valvestem 28 to allow for an amount of lateral movement 114 (see FIG. 1) offlow control element 16 laterally between fluid flow bore inlet end 66and fluid flow bore outlet end 68 such that a pressure applied to inletend 66, represented in FIGS. 1 and 20 by arrow 120, results in lateralmovement 114 of flow control assembly 13 towards the outlet end 68 ofthe fluid flow bore 14 (see FIG. 21) in an amount sufficient to producesealing contact between outer annular surface 93 of outlet valve seat 84with a portion of the valve body 97, and/or such that a pressure appliedto outlet end 68 of fluid flow bore 14 represented in FIGS. 1 and 20 byarrow 121, results in lateral movement 114 of flow control assembly 13towards inlet end 66 of fluid flow bore 14 (see FIG. 20) in an amountsufficient to produce sealing contact between an outer annular surface94 of inlet valve seat 82 and a portion 95 of valve body 12. In anembodiment, distance 112 between the sides 110 of recess 104 aredimensioned relative to distance 113 between the plurality of sides 31of first end 30 to allow for an amount of lateral movement 114 of flowcontrol element 16 between fluid flow bore inlet end 66 and fluid flowbore outlet end 68 of less than or equal to about 0.3 mm, or 0.2 mm or0.1 mm, or 0.05 mm, or 0.01 mm, or 0.005 mm, or 0.001 mm.

In an embodiment, the valve stem comprises a metal alloy heat treated togreater than or equal to about 1034 MPa (150 kpsi) yield as determinedby ASTM C774 or an equivalent thereof.

In an embodiment, at least a portion of a surface of the flow controlelement 16, a surface of the valve stem 28, a surface of the packingbore 32, a surface of the flow bore 14, or any combination thereof has asurface roughness from about 1 to 50 root mean square in micro-inches,or from about 2 to 25 root mean square in micro-inches, or from about 5to 20 root mean square in micro-inches.

In an embodiment, a method comprises providing a bidirectional valveaccording to any one, or any combination of embodiments disclosedherein; rotating the valve stem such that the control element is in theclosed position prior to or after applying a pressurized fluid having apressure of greater than 275.8 MPa (40,000 psi) and a temperature ofgreater than or equal to about 200° C. to the inlet end of the fluidflow bore or to the outlet end of the fluid flow bore and maintainingthe pressure and temperature for at least 1 hour, wherein the fluid ismaintained by the valve without leaking. In an embodiment, the method mycomprise rotating the valve stem such that the control element is in theclosed position and prior to or before rotating the valve stem to closethe valve, applying a pressurized fluid having a pressure of greaterthan 275.8 MPa (40,000 psi), or greater than 310.2 MPa (45,000 psi), orgreater than 344.7 MPa (50,000 psi), at a temperature of greater than orequal to about 200° C., or greater than or equal to about 300° C., orgreater than or equal to about 400° C., to the fluid flow bore, andmaintaining the pressure and temperature for at least 1 hour, or for atleast 5 hours, or for at least 24 hours, wherein the fluid is maintainedby the valve without leaking, or wherein the fluid is maintained by thevalve without leaking after a total of 5 cycles between the “on”position allowing flow and the “off” position which does not allow flow,or wherein the fluid is maintained by the valve without leaking after atotal of 50 cycles, or wherein the fluid is maintained by the valvewithout leaking after a total of 1000 cycles. Accordingly, thebidirectional ball valve according to any one or any combination ofembodiments disclosed herein may be suitable for use under extremelyhigh pressures (i.e., greater than 40,000 psi), and high temperatures(i.e., greater than or equal to about 200° C.).

In an embodiment, a method comprises providing a bidirectional valve avalve body comprising an axial fluid flow bore disposed therethroughhaving an inlet end located opposite an outlet end and a flow controlassembly located within a portion of the fluid flow bore, the flowcontrol assembly comprising a flow control element disposed between, andhaving an outer surface in sealing contact with an inner annular surfaceof an inlet valve seat and an inner annular surface of an outlet valveseat, wherein the flow control element is rotatable between an open anda closed position; a valve stem extending from an outer end through apacking bore disposed radially around the valve stem in the valve bodyto an inner end of the valve stem, wherein the inner end of the valvestem comprises a plurality of sides dimensioned and arranged torotationally engage a corresponding recess having a corresponding numberof sides disposed into the flow control element, wherein a distancebetween the sides of the recess are dimensioned relative to a distancebetween the plurality of sides of the inner end of the valve stem toallow for an amount of lateral movement of the flow control elementlaterally between the fluid flow bore inlet end and the fluid flow boreoutlet end such that a pressure applied to the inlet end of the fluidflow bore results in lateral movement of the flow control assemblytowards the outlet end of the fluid flow bore in an amount sufficient toproduce sealing contact between an outer annular surface of the outletvalve seat with a portion of the valve body, such that a pressureapplied to the outlet end of the fluid flow bore results in lateralmovement of the flow control assembly towards the inlet end of the fluidflow bore in an amount sufficient to produce sealing contact between anouter annular surface of the inlet valve seat and a portion of the valvebody, or a combination thereof, wherein at least a portion of the innerannular surface of the inlet valve seat, the inner annular surface ofthe outlet valve seat, or a combination thereof, comprise a sealing facedimensioned and arranged to sealingly engage a portion of the outersurface of the fluid control element, and wherein at least a portion ofthe inner annular surface of the inlet valve seat, the inner annularsurface of the outlet valve seat, or a combination thereof, comprise aplurality of support surfaces dimensioned and arranged in physicalcontact with the outer surface of the fluid control element adjacent thesealing face; rotating the valve stem such that the control element isin the closed position prior to or after applying a pressurized fluidhaving a pressure of greater than 275.8 MPa (40,000 psi) and atemperature of greater than or equal to about 200° C. to the inlet endof the fluid flow bore or to the outlet end of the fluid flow bore andmaintaining the pressure and temperature for at least 1 hour, whereinthe fluid is maintained by the valve without leaking.

In an embodiment, the method may further comprises a bidirectional valvecomprising a valve stem packing system comprising a plurality of packingrings having an inner diameter dimensioned to be disposable around thevalve stem, and an outer diameter dimensioned to be locatable within aninner diameter of the packing bore disposed radially around the valvestem in the valve body, wherein the packing system comprises athermoplastic ring assembly sandwiched between, and in physical contactwith a sealing ring assembly sandwiched between, and in physical contactwith an anti-extrusion ring assembly and the valve body, wherein thethermoplastic ring assembly comprises at least one thermoplastic ringhaving an inner diameter dimensioned and arranged to sealingly engagethe valve stem and an outer diameter dimensioned and arranged tosealingly engage the inner diameter of the packing bore, and opposingannular surfaces dimensioned and arranged to physically engage annularsurfaces of the sealing ring assembly; wherein the sealing ring assemblycomprises an outer sealing ring having an inner annular surface inphysical contact with an outer annular surface of the thermoplastic ringassembly, and an inner sealing ring having an outer annular surface inphysical contact with an inner annular surface of the thermoplastic ringassembly, wherein each sealing ring has an inner diameter dimensionedand arranged to sealingly engage the valve stem and an outer diameterdimensioned and arranged to sealingly engage the inner diameter of thepacking bore; wherein the anti-extrusion ring assembly comprises atleast one upper anti-extrusion ring having an inner annular surface inphysical contact with an outer annular surface of the outer sealingring; wherein the sealing rings have a hardness which is greater than ahardness of the at least one thermoplastic ring, and wherein theanti-extrusion ring has a hardness which is greater than a hardness ofthe sealing rings.

Embodiments

Accordingly, the instant disclosure relates to the followingembodiments:

-   -   A. A bidirectional valve comprising:    -   a valve body comprising an axial fluid flow bore disposed        therethrough having an inlet end located opposite an outlet end        and a flow control assembly located within a portion of the        fluid flow bore; the flow control assembly comprising a flow        control element disposed between, and having an outer surface in        sealing contact with an inner annular surface of an inlet valve        seat and an inner annular surface of an outlet valve seat, the        flow control element is rotatable between an open and a closed        position;    -   a valve stem extending from an outer end through a packing bore        disposed radially around the valve stem in the valve body to an        inner end of the valve stem, the inner end of the valve stem        comprising a plurality of sides dimensioned and arranged to        rotationally engage a corresponding recess having a        corresponding number of opposing sides disposed into the flow        control element, a distance between the sides of the recess are        dimensioned relative to a distance between the plurality of        sides of the first end of the valve stem to allow for an amount        of lateral movement of the flow control element between the        fluid flow bore inlet end and the fluid flow bore outlet end        such that a pressure applied to the inlet end of the fluid flow        bore results in lateral movement of the flow control assembly        towards the outlet end of the fluid flow bore in an amount        sufficient to produce sealing contact between an outer annular        surface of the outlet valve seat with a portion of the valve        body, and such that a pressure applied to the outlet end of the        fluid flow bore results in lateral movement of the flow control        assembly towards the inlet end of the fluid flow bore in an        amount sufficient to produce sealing contact between an outer        annular surface of the inlet valve seat and a portion of the        valve body, or a combination thereof.    -   B. The bidirectional valve of embodiment A, wherein at least a        portion of the inner annular surface of the inlet valve seat,        the inner annular surface of the outlet valve seat, or a        combination thereof, comprise a sealing face dimensioned and        arranged to sealingly engage a portion of the outer surface of        the fluid control element, and wherein at least a portion of the        inner annular surface of the inlet valve seat, the inner annular        surface of the outlet valve seat, or a combination thereof,        comprise a plurality of support surfaces dimensioned and        arranged in physical contact with the outer surface of the fluid        control element adjacent the sealing face.    -   C. The bidirectional valve of embodiment A or B, wherein the        valve stem further comprises a shoulder with an enlarged outer        diameter formed on the valve stem wherein the outside diameter        of the shoulder is greater than an inside diameter of a portion        of the valve body, a portion of a bracket attached to the valve        body, a bushing attached to the valve body, or a combination        thereof disposed around the valve stem between the outer end of        the valve stem and the shoulder.    -   D. The bidirectional valve of any one of embodiments A-C,        wherein the inner valve seat, the outer valve seat, or a        combination thereof comprise a plurality of vent grooves        laterally disposed into the inner annular surface of the valve        seat between each of the plurality of support surfaces and an        outer radial edge of the valve seat, an inner radial edge of the        valve seat, or a combination thereof.    -   E. The bidirectional valve of any one of embodiments A-D,        wherein at least a portion of the outer surface of the flow        control element, the inner surface of the packing bore, the        fluid flow bore, the valve stem, the inner annular surface of        the inlet valve seat, the outer annular surface of the inlet        valve seat, the inner annular surface of the outlet valve seat,        the outer annular surface of the outlet valve seat, or a        combination thereof includes a spray and fuse coating comprising        metals from Groups 6-12 of the periodic table of the elements        alone, or in compounds comprising elements from Groups 13-16 of        the period table of the elements.    -   F. The bidirectional valve of any one of embodiments A-E,        wherein at least one of the inner valve seat or the outer valve        seat is attached to the valve body using a plurality of threaded        members engaged with an outer radial edge of the valve seat and        the valve body.    -   G. The bidirectional valve of any one of embodiments A-F,        wherein at least a portion of an outer surface of the flow        control element, a surface of the valve stem, a surface of the        packing bore, a surface of the fluid flow bore, a surface of the        valve seat, or a combination thereof has a surface roughness        from about 1 to 50 root mean square in micro-inches.    -   H. The bidirectional valve of any one of embodiments A-G,        further comprising a valve stem packing system comprising:    -   a plurality of packing rings having an inner diameter        dimensioned to be disposable around the valve stem, and an outer        diameter dimensioned to be locatable within an inner diameter of        the packing bore disposed radially around the valve stem in the        valve body, wherein the packing system comprises:    -   a thermoplastic ring assembly sandwiched between, and in        physical contact with a sealing ring assembly sandwiched        between, and in physical contact with an anti-extrusion ring        assembly and the valve body, wherein the thermoplastic ring        assembly comprises at least one thermoplastic ring having an        inner diameter dimensioned and arranged to sealingly engage the        valve stem and an outer diameter dimensioned and arranged to        sealingly engage the inner diameter of the packing bore, and        opposing annular surfaces dimensioned and arranged to physically        engage annular surfaces of the sealing ring assembly;    -   wherein the sealing ring assembly comprises an outer sealing        ring having an inner annular surface in physical contact with an        outer annular surface of the thermoplastic ring assembly, and an        inner sealing ring having an outer annular surface in physical        contact with an inner annular surface of the thermoplastic ring        assembly, wherein each sealing ring has an inner diameter        dimensioned and arranged to sealingly engage the valve stem and        an outer diameter dimensioned and arranged to sealingly engage        the inner diameter of the packing bore;    -   wherein the anti-extrusion ring assembly comprises at least one        upper anti-extrusion ring having an inner annular surface in        physical contact with an outer annular surface of the outer        sealing ring;    -   wherein the sealing rings have a hardness which is greater than        a hardness of the at least one thermoplastic ring, and wherein        the anti-extrusion ring has a hardness which is greater than a        hardness of the sealing rings.    -   I. The bidirectional valve of any one of embodiments A-H,        wherein the anti-extrusion ring assembly further comprises an        inner anti-extrusion ring having an outer annular surface in        physical contact with an inner annular surface of the inner        sealing ring and an outer annular surface in physical contact        with the valve body.    -   J. The bidirectional valve of any one of embodiments A-I,        wherein the inner annular surface of the outer anti-extrusion        ring, the outer annular surface of the inner anti-extrusion        ring, or both comprise a chamfer disposed along an outer radial        edge of the anti-extrusion ring.    -   K. The bidirectional valve of any one of embodiments A-J,        wherein the thermoplastic ring assembly comprises a plurality of        individual thermoplastic rings sandwiched between the outer        sealing ring and the inner sealing ring.    -   L. The bidirectional valve of any one of embodiments A-K,        wherein the at least one thermoplastic ring and the sealing        rings individually comprise an engineering thermoplastic        selected from the group consisting of a polycarbonate resin, a        polyamide resin, a polyester resin, a polyether ether ketone        resin, a polyacrylate resin, a polybutylene naphthalate resin, a        liquid crystal polyester, a polyoxalkylene diimide        diacid/polybutyrate terephthalate copolymer, a nitrile resin,        polyoxymethylene resin, a styrene-acrylonitrile copolymer, a        methacrylonitrile-styrene copolymer, a        methacrylonitrile-styrene-butadiene copolymer; an acrylate        resin, a polyvinyl acetate, a polyvinyl alcohol, a chloride        resin, a fluoride resin, a cellulose resin, a polyimide resin, a        polysulfone resin, a polyacetal resin, a polylactone resin, a        polyketones, a polyphenylene oxide resin, a polyphenylene        oxide/polystyrene resin, a polyphenylene sulfide resin, a        styrene resin, an acrylonitrile-butadiene-styrene resin, a        polyolefin resin, and a combination thereof.    -   M. The bidirectional valve of any one of embodiments A-L,        wherein the at least one thermoplastic ring comprises polyvinyl        fluoride (PVF), polychlorofluoroethylene (PCFE),        polytetrafluoroethylene (PTFE), or a combination thereof.    -   N. The bidirectional valve of any one of embodiments A-M,        wherein the sealing rings individually comprise a polyamide        resin, a polyphenylene oxide/polystyrene resin, a        polyoxymethylene resin, a polyether ether ketone, or a        combination thereof.    -   O. The bidirectional valve of any one of embodiments A-N,        wherein the at least one thermoplastic ring has a Rockwell R        hardness determined according to ASTM D785 or an equivalent        thereof, of less than or equal to about 100 R, and wherein the        sealing ring has a Rockwell R hardness of greater than about 100        R.    -   P. The bidirectional valve of any one of embodiments A-O,        wherein a Rockwell R hardness of the sealing rings is greater        than the Rockwell R hardness of the at least one thermoplastic        ring by at least about 50 R units, wherein the Rockwell R        hardness is determined according to ASTM D785, or an equivalent        thereof.    -   Q. The bidirectional valve of any one of embodiments A-P,        wherein the at least one anti-extrusion ring comprises brass,        steel, titanium, silicon carbide, an at least partially        austenitic steel alloy, or a combination thereof.    -   R. The bidirectional valve of any one of embodiments A-Q,        wherein the at least one anti-extrusion ring comprises an        austenitic steel alloy comprising iron, chromium, nickel,        manganese, silicone, and nitrogen.    -   S. The bidirectional valve of any one of embodiments A-R,        wherein a fluid applied to the fluid flow bore is maintained by        the valve in the closed position without leaking for at least        one hour, wherein the applied fluid has a pressure of greater        than 275.8 MPa (40,000 psi) and a temperature of greater than or        equal to about 200° C.    -   T. A method comprising:        providing any one of the a bidirectional valves of embodiments        A-R,    -   rotating the valve stem such that the control element is in the        closed position prior to or after applying a pressurized fluid        having a pressure of greater than 275.8 MPa (40,000 psi) and a        temperature of greater than or equal to about 200° C. to the        inlet end of the fluid flow bore or to the outlet end of the        fluid flow bore and maintaining the pressure and temperature for        at least 1 hour, wherein the fluid is maintained by the valve        without leaking.    -   U. A method comprising:    -   providing a bidirectional valve comprising:    -   a valve body comprising an axial fluid flow bore disposed        therethrough having an inlet end located opposite an outlet end        and a flow control assembly located within a portion of the        fluid flow bore,    -   the flow control assembly comprising a flow control element        disposed between, and having an outer surface in sealing contact        with an inner annular surface of an inlet valve seat and an        inner annular surface of an outlet valve seat, wherein the flow        control element is rotatable between an open and a closed        position;    -   a valve stem extending from an outer end through a packing bore        disposed radially around the valve stem in the valve body to an        inner end of the valve stem, wherein the inner end of the valve        stem comprises a plurality of sides dimensioned and arranged to        rotationally engage a corresponding recess having a        corresponding number of sides disposed into the flow control        element, wherein a distance between the sides of the recess are        dimensioned relative to a distance between the plurality of        sides of the first end of the valve stem to allow for an amount        of lateral movement of the flow control element laterally        between the fluid flow bore inlet end and the fluid flow bore        outlet end such that a pressure applied to the inlet end of the        fluid flow bore results in lateral movement of the flow control        assembly towards the outlet end of the fluid flow bore in an        amount sufficient to produce sealing contact between an outer        annular surface of the outlet valve seat with a portion of the        valve body, and such that a pressure applied to the outlet end        of the fluid flow bore results in lateral movement of the flow        control assembly towards the inlet end of the fluid flow bore in        an amount sufficient to produce sealing contact between an outer        annular surface of the inlet valve seat and a portion of the        valve body, or a combination thereof, and    -   rotating the valve stem such that the control element is in the        closed position prior to or after applying a pressurized fluid        having a pressure of greater than 275.8 MPa (40,000 psi) and a        temperature of greater than or equal to about 200° C. to the        inlet end of the fluid flow bore or to the outlet end of the        fluid flow bore and maintaining the pressure and temperature for        at least 1 hour, wherein the fluid is maintained by the valve        without leaking.    -   V. The method of any one of embodiments T or U, wherein at least        a portion of the inner annular surface of the inlet valve seat,        the inner annular surface of the outlet valve seat, or a        combination thereof, comprise a sealing face dimensioned and        arranged to sealingly engage a portion of the outer surface of        the fluid control element, and wherein at least a portion of the        inner annular surface of the inlet valve seat, the inner annular        surface of the outlet valve seat, or a combination thereof,        comprise a plurality of support surfaces dimensioned and        arranged in physical contact with the outer surface of the fluid        control element adjacent the sealing face.    -   W. The method of any one of embodiments T-V, wherein the        bidirectional valve further comprises a valve stem packing        system comprising:    -   a plurality of packing rings having an inner diameter        dimensioned to be disposable around the valve stem, and an outer        diameter dimensioned to be locatable within an inner diameter of        the packing bore disposed radially around the valve stem in the        valve body, wherein the packing system comprises:    -   a thermoplastic ring assembly sandwiched between, and in        physical contact with a sealing ring assembly sandwiched        between, and in physical contact with an anti-extrusion ring        assembly and the valve body,    -   wherein the thermoplastic ring assembly comprises at least one        thermoplastic ring having an inner diameter dimensioned and        arranged to sealingly engage the valve stem and an outer        diameter dimensioned and arranged to sealingly engage the inner        diameter of the packing bore, and opposing annular surfaces        dimensioned and arranged to physically engage annular surfaces        of the sealing ring assembly;    -   wherein the sealing ring assembly comprises an outer sealing        ring having an inner annular surface in physical contact with an        outer annular surface of the thermoplastic ring assembly, and an        inner sealing ring having an outer annular surface in physical        contact with an inner annular surface of the thermoplastic ring        assembly, wherein each sealing ring has an inner diameter        dimensioned and arranged to sealingly engage the valve stem and        an outer diameter dimensioned and arranged to sealingly engage        the inner diameter of the packing bore;    -   wherein the anti-extrusion ring assembly comprises at least one        upper anti-extrusion ring having an inner annular surface in        physical contact with an outer annular surface of the outer        sealing ring,    -   wherein the sealing rings have a hardness which is greater than        a hardness of the at least one thermoplastic ring, and wherein        the anti-extrusion ring has a hardness which is greater than a        hardness of the sealing rings.

The invention is described above in reference to specific examples andembodiments. The metes and bounds of the invention are not to be limitedby the foregoing disclosure, which is illustrative only, but should bedetermined in accordance with the full scope and spirit of the appendedclaims. Various modifications will be apparent to those skilled in theart in view of the description and examples. It is intended that allsuch variations within the scope and spirit of the appended claims beembraced thereby.

1-36. (canceled)
 37. A valve comprising: a valve body comprising a fluidflow bore disposed therethrough having an inlet end, an outlet end and aflow control assembly located within a portion of the fluid flow bore;the flow control assembly comprising a flow control element disposedbetween, and having an outer surface in sealing contact with an innerannular surface of an inlet valve seat and an inner annular surface ofan outlet valve seat, wherein the flow control element is rotatablebetween an open and a closed position; a valve stem extending from anouter end through a packing bore disposed radially around the valve stemin the valve body to an inner end of the valve stem, wherein the innerend of the valve stem rotationally engages a recess disposed in the flowcontrol element; an outlet sealing face on a portion of the innerannular surface of the outlet valve seat dimensioned and arranged tosealingly engage a portion of the outer surface of the fluid flowcontrol element; a first plurality of support surfaces adjacent theoutlet sealing face dimensioned and arranged in physical contact withthe outer surface of the fluid flow control element; and a firstplurality of respective vent grooves disposed between adjacent ones ofthe first plurality of support surfaces, and between the first pluralityof support surfaces and the outlet sealing face.
 38. The valve of claim37, further comprising: an inlet sealing face on a portion of the innerannular surface of the inlet valve seat dimensioned and arranged tosealingly engage a portion of the outer surface of the fluid flowcontrol element; a second plurality of support surfaces adjacent theinlet sealing face dimensioned and arranged in physical contact with theouter surface of the fluid flow control element; and a second pluralityof respective vent grooves disposed between adjacent ones of the secondplurality of support surfaces, and between the first plurality ofsupport surfaces and the outlet sealing face.
 39. The valve of claim 37,wherein the inner end of the valve stem comprises a plurality of sides,the recess in the flow control element has a corresponding number ofopposing sides, and distances between the sides of the inner end of thevalve stem and the opposing sides of the recess are dimensioned to allowfor an amount of lateral movement of the flow control element betweenthe fluid flow bore inlet end and the fluid flow bore outlet end suchthat a pressure applied to the inlet end of the fluid flow bore resultsin lateral movement of the flow control assembly towards the outlet end.40. The valve of claim 39, wherein the lateral movement of the fluidflow bore allows sealing contact between an outer annular surface of theoutlet valve seat and the valve body when pressure is applied to theinlet end, and sealing contact between an outer annular surface of theinlet valve seat and the valve body when pressure is applied to theoutlet end of the fluid flow bore.
 41. The valve of claim 37, furthercomprising a spray and fuse coating on the outlet sealing face and thefirst plurality of support surfaces, the spray and fuse coatingcomprising metals from Groups 6-12 of the periodic table of the elementsalone, or in compounds comprising elements from Groups 13-16 of theperiodic table of the elements.
 42. The valve of claim 38, furthercomprising a spray and fuse coating on the inlet and outlet sealingfaces and the first and second plurality of support surfaces, the sprayand fuse coating comprising metals from Groups 6-12 of the periodictable of the elements alone, or in compounds comprising elements fromGroups 13-16 of the periodic table of the elements.
 43. The valve ofclaim 37, further comprising a shoulder on the valve stem with anenlarged outer diameter formed on the valve stem wherein the outsidediameter of the shoulder is greater than an inside diameter of a portionof the valve body, a portion of a bracket attached to the valve body, abushing attached to the valve body, or a combination thereof disposedaround the valve stem between the outer end of the valve stem and theshoulder.
 44. The valve of claim 37, wherein the outlet valve seat isattached to the valve body using a plurality of threaded members,radially spaced about an outer radial edge of the outlet valve seat, andengaged with the outlet valve seat and the valve body.
 45. The valve ofclaim 44, further comprising a spring to bias the inlet valve seatagainst the flow control element.
 46. The valve of claim 37, furthercomprising a valve stem packing system comprising: a plurality ofpacking rings disposed in the packing bore, the packing rings having aninner diameter disposed around the valve stem and an outer diameterdisposed adjacent a cylindrical surface of the packing bore; an inneranti-extrusion ring in the packing bore between the packing rings and aninner end of the packing bore; and an outer anti-extrusion ring in thepacking bore between the packing rings and a packing gland.
 47. A methodcomprising: locating a flow control assembly in a fluid flow boredisposed through a valve body, the fluid flow bore having an inlet endand an outlet end, the flow control assembly comprising a flow controlelement disposed between inlet and outlet valve seats and having anouter surface for sealing contact with an inner annular surfaces of theinlet and outlet valve seats; rotating the flow control element betweenopen and closed positions; forming a seal between a sealing face of theinner annular surface of the outlet valve seat and the outer surface ofthe fluid flow control element; physically contacting the outer surfaceof the flow control element with a first plurality of support surfaceslocated on the inner annular surface adjacent the sealing face of theoutlet valve seat; separating adjacent ones of the first plurality ofsupport surfaces with a like plurality of vent grooves on the innerannular surface of the outlet valve seat between adjacent ones of thefirst plurality of support surfaces; separating the first plurality ofsupport surfaces from the sealing face of the outlet seal with anannular vent groove on the inner annular surface of the outlet valveseat between the respective sealing face and the support surfaces; andapplying a pressurized fluid to the inlet end of the fluid flow bore toform a fluid seal between the flow control element, the outlet valveseat and the valve body.
 48. The method of claim 47, further comprisingmaintaining the pressurized fluid applied to the inlet end at a pressureof greater than 275.8 MPa (40,000 psi) and a temperature of greater thanor equal to about 200° C. for at least 1 hour without leaking past theflow control element into the outlet end of the fluid flow bore.
 49. Themethod of claim 47, further comprising: forming a seal between a sealingface of the inner annular surface of the inlet valve seat and the outersurface of the fluid flow control element; physically contacting theouter surface of the flow control element with a second plurality ofsupport surfaces located on the inner annular surface adjacent thesealing face of the inlet valve seat; separating adjacent ones of thesecond plurality of support surfaces with a like plurality of ventgrooves on the inner annular surface of the inlet valve seat betweenadjacent ones of the second plurality of support surfaces; separatingthe second plurality of support surfaces from the sealing face of theinlet seal with an annular vent groove on the inner annular surface ofthe inlet valve seat between the respective sealing face and the supportsurfaces; and applying a pressurized fluid to the outlet end of thefluid flow bore to form a fluid seal between the flow control element,the inlet valve seat and the valve body.
 50. The method of claim 49,wherein an inner end of a valve stem comprises a plurality of sides toengage a recess in the flow control element having a correspondingnumber of opposing sides, and distances between the sides of the innerend of the valve stem and the opposing sides of the recess aredimensioned to allow for an amount of lateral movement of the flowcontrol element between the fluid flow bore inlet end and the fluid flowbore outlet end such that a pressure applied to the inlet end of thefluid flow bore results in lateral movement of the flow control assemblytowards the outlet end.
 51. The method of claim 50, further comprisingpreventing blowout of the stem with a shoulder having an enlarged outerdiameter formed on the valve stem wherein the outside diameter of theshoulder is greater than an inside diameter of a portion of the valvebody, a portion of a bracket attached to the valve body, a bushingattached to Page 8 the valve body, or a combination thereof, disposedaround the valve stem between the outer end of the valve stem and theshoulder.
 52. The method of claim 47, further comprising spraying andfusing a coating on the outlet sealing face and the first plurality ofsupport surfaces, the spray and fuse coating comprising metals fromGroups 6-12 of the periodic table of the elements alone, or in compoundscomprising elements from Groups 13-16 of the periodic table of theelements.
 53. The method of claim 52, further comprising spraying andfusing a coating on the inner annular surface of the inlet valve seat,the spray and fuse coating comprising metals from Groups 6-12 of theperiodic table of the elements alone, or in compounds comprisingelements from Groups 13-16 of the periodic table of the elements. 54.The method of claim 47, further comprising attaching the outlet valveseat to the valve body using a plurality of threaded members, radiallyspaced about an outer radial edge of the outlet valve seat, and engagedwith the outlet valve seat and the valve body.
 55. The method of claim47, further comprising biasing the inlet valve seat against the flowcontrol element.